Can cap and closure.



E. M. LANG, JR.

GAN GAP AND CLOSURE.

APPLICATION FILED AUG. 3, 1909.

1,122,954. Patented 1 )ec.29, 1914.

2 SHEBTSSHBET 1..

E. M. LANG, JR.

CAN GAP AND CLOSURE.

APPLICATION FILED AUG. 3, 1909.

1, 122,954. I Patented Dec. 29, 1914.

2 SHEBTSSHEET 2.

W ii 1, 11 n EDWARD M. Lane, .13., or PORTLAND, MAINE.

CAN car AND CLOSURE.

Specification of Letters Patent.

Application filed August 3, 1909. Serial No. 511,060. g

To all whom it may concern Be it known that I, EDWARD M. LANG, J r., a citizen of the United States, residing at Portland, in the county of Cumberland and State of Maine, have invented certain new and useful Improvements in Can Caps and Closures; and I do-hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled inthe art to which it appertains to make and use the same.

My invention relates to can caps and closures.

In making ordinary tin cans a circular hole is made in the upper end leaving a raw edge, such cans being made of iron or steel coated with tin. Around this raw edge is a groove into which the can cap fits. The said cap has the usual central perforation or vent hole made by puncturing a hole through the tin, leaving a ragged raw edge projecting downwardly about one eighth of an inch which oftentimes. brings the projection of the vent hole in contact with the contents of the can. At present, the common method is to place such a, cap having a depending edge in the groove on the top of the can,and then solder it in. This method, however,is open to various'ob ections. 30

In soldering the tops on cans a soldering fluid is almost invariably used which contains hydrochloric acid. In the process of applying heat to the cap to be soldered the flux sweats through between the depending edge of the cap and the can top and the solder follows it. The result is that the flux attacks the raw edge of the can top which the solder does not coverby present methods, but spreads over the under surface of the cap. The action of the flux upon the raw edge of the can top' -is sure to cause corrosion and in some nstances the .con- 1 tents of the can attack this raw edge causing discoloration of said contents. The same objection applies to the downwardly-projecting raw edge of the vent hole in the can cap. Of course, this injures the sale of the goods and injures the'reputation of the can- "ner, and it has long been recognized as a great desideratum to devise some economical and efi'ectual Way of preventing this corrosion and discoloration.

My invention has for its object to produce a can cap and closure without departing from the groove form of opening in the can top, so that neither the flux used in the process of soldering, nor the contents of the can, can produce discoloration by attacking the exposed edge of the plate in the top of the can or the raw edge of the perforation in the can cap.

With this object in view my invention consists in the construction and combination of parts, as hereinafter described and claimed.

In the accompanying drawings: Figure 1 is a plan view showing the top of a can with my invention applied thereto; Fig. 2

is a longitudinal section of .my improved can cap; Fig. 3 is a longitudinal section of the top of the can, the dotted line between Figs. 2 and 3 indicating how the cap is to be placed in the groove of the can top; Fig.

4 1s a section on an enlarged scale of the outer part of a can cap, showing the fiuxed :solder hem thereon; Fig. 5 is a top plan view of the same; Fig. 6 is a section on a larger scale, showing part of a can top and part of a cap resting thereon; Fig. 7 is a View similar to Fig. 6, but showing the cap soldered to the can top and with the solder covering the raw edge. Fig. 8 is a cross section of astud top can, showing the cap or cover in position to be applied; Fig. 9 is a cross section on an enlarged scale through the central portion of a can cap or cover, showing the preferred manner of making the vent hole; Fig.,l0 is a similar View, showing the same after the vent hole has been soldered; and Fig. 11 is a top plan view of the part shown in Fig. 9, showing the knurling of the small solder ring.

1 indicates an ordinary can top, having 'a downwardly disposed portion 1 and an upwardly disposed and straight marginal rim 1"- and providing between' them an annular groove 2. The closure is cut away to provide a central opening 3, and this leaves the edge 4 in a rough condition, or raw. 5 indicates the cap, highest in the center,- as usual, and having an upturned portion 5* and terminating in a downwardly projecting edge or rim 6. The portions 5 and 6 provide an inverted groove which receives the rim 1 and in like manner the groove between the portions 1? and 1' receives the projecting edge or rim 6. Preferably this edge is covered by a hem of solder 7, having flux 8 in its interior. The cap 5 is also provided with a downwardly projecting groove,

Patented Dec. 29, 1914i.

leaving a ridge 9 on the interior of the cap, said ridge being provided with sloping sides, so that when the cap is placed on the cap top, it will fit tightly against the edge 4, which perfectly centers the cap, the hem 6 fitting down into the groove 2. In the ordinary form of applying the cap to the can cover, the outside edge of the cap,

whether hemmed with solder or not, fits loosely in the groove 2, and in soldering the same together, some part of the raw edge 4 is left exposed, which, however, does not occur in my invention. The upper and lower surfaces of thesolder hem 7 are preferably knurled, as shown at 10, in Fig. 5.

The ordinary way of forming a vent hole is simplyto make a punctured hole in the top of the cap or cover with the ragged ends projecting downwardly. I prefer to insert the puncturing tool from-beneath, so that the ragged ends will project upwardly as shown in Fig. 8, but in someinstanoes it is better to cut out a small portion of the central part of the cap or cover, leaving a circular hole as indicated more clearly in Fig. 9. In other words, the cap is provided with a central circular recess, the same in miniature as the opening in the can top. I do not restrict myself, however, to a perforation having a recess around it, nor to the shape of the perforation.

Referring to Figs. 8 to 11, 11 represents a can cover having a central hole punched upwardly through it, leaving a raw edge 12, as shown in Fig. 8, or instead asmall circular disk may be out out, leaving an opening 13, as shown in Fig. 9. In either case, however, when the opening is made in'the can cover, the central part is depressed and then bent upwardly, as shown at 14, leaving a groove, and in this groove a small ring of solder 15 is placed, which ring is preferably knurled as shown at 16 in Fig. 11. In Figs. 8 to 11, a complete can cover is shown, but in Figs. 1 and 2 a can cap is shown with the vent hole made and hemmed as described.

Referring to Fig. 8, 17 represents the body. of a stud top can more especially designed for use by fruit and vegetable packers. It consists of a cylinder of tin open at both ends and having the upper and lower edges bent first downwardly and then upwardly at the top, leaving the groove 18, and bent reversely at the bottom, leaving a similar groove. The solid bottom 19 is made precisely like the top 11, except that it has no vent hole and is soldered to the bottom of the can, forming a complete solder joint exactly similar to the one shown in Fig. 7. The cap 11 is adapted to fit down into the top of the can with its edge in the groove18, and said cap is made precisely like the can cap shown in Figs. 1 to 5, except that it is larger.

In Fig. 10, the vent hole is shown after the soldering operation, the solder 20, as shown, completely covering the raw edge of the vent hole. According to my invention, therefore, both the edges of the vent hole, the edges of the can cover 5, and the edges of the can top surrounding the groove 18 are, after the soldering operation is finished, completely covered with solder, so that it is impossible for the contents of the can to reach QJZELW edge, thus effectively preventing corrosion and discoloration. In this way, less solder is required, because, as is well known, the closer you can get two plain surfaces of tin together, the less is the solder needed. On account of the downwardly-projecting ridge on the under side of the cap, the process of soldering does not cause the solder and flux to spread over the under surface of the cap after sweating through, as heretofore, for the reason that the solder and flux are arrested by said ridge and confined in the interior recess of the cap, thereby completely covering with solder the raw edge of the can top. F urthermore, the raw edge of the vent hole of the cap being turned outwardly is completely covered with solder in the soldering operation. The result is that a stronger seal is assured with the smallest possible amount of solder. As the vent hole does not come in contact with the contents of the can, there is nothing to interfere with the art of soldering. The flux and the solder are less liable than heretofore to get into the contents of the can thr )ugh the opening, as the flux and solder are applied to the recess instead of in the vent hole. The solder when molten in the recess of the cap forms a solder cap seal for the opening, with a uniform amount of solder. Caps made with a vent hole as outlined in this application can be easily separated, one by one, whereas, with the ordinary cap the vent hole projection contacts so closely when nested one upon another, that the irregular ragged edges sometimes cause the caps to stick together, so that it is almost impossible to separate them one at a time, either for the purpose of hemming them with solder, or placing them in the groove after the can has been filled and is ready to be soldered. There is no raw edge exposed to the action of the flux or contents of the can, so that the usual undesirable discoloration from this cause is entirely eliminated, making an absolutely sanitary hermetic closure. I do not restrict myself to the use of this particular form of cap and vent hole in the I same cap, as either of these features may be employed independently.

I claim 2- A closure for vessels having a depressed portion on the exterior thereof with a vent an annular groove adapted to receive a seal-' ing composition for closing said vent opening, substantially as described. 3

In testimony whereofQI aflix my signature, 1n presence of two vvltnesses.

. 'EDWARD M. L Witnesses: 4

JAMES R. PARSONS,'

ALDEN STRONG.

ANG, in V 

